Toshiba TC-net Instruction Manual page 76

5. Dual Function
5.1.3. At the case of more than three OPC Servers (1 : 1 Backup)
At the case of 1 : 1 backup,
when ST1 becomes abnormal, ST2 backups ST1
when ST2 becomes abnormal, ST3 backups ST2
....
when STn becomes abnormal, ST1 backups STn..
But one node doesn't backup plural nodes. (When ST1 and ST2 become abnormal, ST2 is
backed up by ST3 but ST1 isn't backed up by any node. )
-> This system can't support the abnormal status of neighbor nodes.
OPC Server
(ST1)
nVCON
5.1.4. At the case of more than three OPC Servers (N : 1 Backup)
At the case of N : 1 backup,
when ST1,ST2 ... and STn become abnormal, STx backups all abnormal nodes
Plural nodes can backup one node. ( When ST1 and ST2 become abnormal, another node
backups these two nodes.)
OPC Server
(ST1)
nVCON
68
Client
Client
OPC Server
(ST2)
...
nVCON
Client Client
OPC Server
(ST2)
...
nVCON
...
Client
OPC Server OPC Server
...
(ST3)
...
nVCON nVCON
...
Client
OPC Server
...
(STn)
...
nVCON
Ethernet
(STn)
TC-net
Ethernet
OPC Server
(STx)
TC-net
nVCON